Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 520 [Rate centres in NPA 520] [Dial plan for NPA 520]

NXX: 337

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-337 A Willcox AZ TCSNAZMAVMD  3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 668      
520-337 0 Willcox AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 668   2015-01-09   
520-337 1 Willcox AZ   630E ONVOY, LLC - AZ 668   2013-03-22   
520-337 2 Willcox AZ   630E ONVOY, LLC - AZ 668   2012-05-18   
520-337 3 Willcox AZ   630E ONVOY, LLC - AZ 668   2014-10-22   
520-337 4 Willcox AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 668   2014-10-11   
520-337 5 Willcox AZ   630E ONVOY, LLC - AZ 668   2013-01-10   
520-337 6 Willcox AZ   630E ONVOY, LLC - AZ 668   2013-01-10   
520-337 7 Willcox AZ   630E ONVOY, LLC - AZ 668   2013-01-10   
520-337 8 Willcox AZ   630E ONVOY, LLC - AZ 668   2013-01-10   
520-337 9 Willcox AZ   630E ONVOY, LLC - AZ 668   2013-01-10   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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